イトミミズを用いた急性毒性試験とその評価

抄録

The LC₅₀ test method by use of Tubifex was developed for the evaluation of eco-toxicity of chemicals. The change of the observation period, the size of Tubifex or the test temperature affected little the LC₅₀ value of 3, 5-dichlorophenol. Acute toxicity of 20 chemicals was tested at 20°C for 48 h by use of Tubifex of 30-50 mm in length. The test results were compared with the other three biological test methods ; EC₅₀ of activated sludge respiration inhibition test, LC₅₀ of Oryzias latipes (Himedaka ; red killifish) acute toxicity test and EC₅₀ of Tetrahymena pyriformis proliferation inhibition test. A good correspondence was found in each two test method compared, and the regression analysis showed that the sensitivity of the Tubifex test lied between those of activated sludge and O. latipes tests.